Lapping machine



Dec. 18, 1934.

W. P. HUNT LAPPING MACHINE Filed 9ct. 17, 1927 IDM/ENTOR. B" 9kb@ 7L MVM.

Patented Dec. 18, 1934 PATENT ori-ICE LAPPING MACHINE wilson r. nant, Moline, m.. signor 1 mitte Engineering Company, Inc., Detroit, Mich. j

'Application october 17, 1921, serial No. 226,117 s owms.` (c1. 511s4.3)

My invention has reference to lapping machines of that particular type which is set forth in my former application' for Letters Patent of the United States filed May 5, 1927, Serial No. 188,957,

which has matured into Patent No. 1,793,486, issued February 24, 1931. The present invention has to do more with the grinding tool, and means for support and operation of the grinding elements thereof. Such parts are supported and actuated so as to be capable of a very delicate adjustment in the progress of the work, and are Swingingly mounted so as to possess perfect freedom of action.

In the drawing:

Fig. 1 is a side elevation, partly in section, of

' one of the tools and its support.

Fig. 2 is a vertical section of the grinding or polishing head.

Fig. 3 is a horizontal cross-section on the broken une a-s of Fig. 2.

Machines ofthe type mentioned are usually of a multiple character, each mounted in a head, as

' indicated at 1, supported so as to be capable of vertical movement. In said head is rotatably supporteda spindle 2, provided with a worm 3, to be driven by a worm gear 4 on a shaft 5, to give to the spindle 'the usual rotary action. Fixed to the lower end of said spindle is a coupling 6, to

3o polishing head, consisting of a cylinder 7, fixed to the upper end of which is a dome-shaped cap 8. 'I'he coupling 6 and cap 8 are connected by means of a spherical member 6* on the lower end of the coupling and in a similar space in said cap and the upper end of the cylinder 7, the coupling and member 6* being united by a pin 6b having ends projecting into recesses 8 in the inner face of the cap 8. A set of frames 9 is supported from said cylinder, by means of arms 10 near the ends of said frames provided with sleeves 11, pivoted on pins 12 connected with the cylinder 7.

Each ofthe frames 9 is longitudinally channelled to receive a stone or grinding element 13, the outer faces of which are equldistant from the center of the tool, and shaped to conform to the surface of the inner wall of a cylinder. Midway its ends each of said frames is provided with a follower 14, the inner plane face of which is offset radially from the median line of the frame and has a radially offset bearing against a cone r15, attached to the lower end of a rod 16, which rod projects upwardly through the spindle 2, and a distance above the upper end thereof. The con- 55 nectionbetweentherodlandcone 15is ofa the lower end of which is attached a grinding or modified ball and socket type, the curved end 16 of said rod entering a recess 15 in the upper end of the cone member, and the parts being secured by a pin 15b passing through the end of said rod and the cone member. This lends a limited 5 amount of flexibility to the joint between said parts. The inner ends of the followers 14 are beveled to conform to the shape of the cone, and a. downward movement of the cone tends to force said followers and the frames!) outwardly, while an upward movement of the cone permits a reverse action of the frames.

Above the upper end of the rod 16 is an arm 17, xed on a shaft 18, rockingly mounted in a support 19, projected from the main machine. 15 In the outer end of the arm 17 is a threaded pin 20, provided with a thumb-turn 21, the lower end of said pin bearing against the end of the rod 16,

which is held yieldinglyV in raised position by means of a coiled spring 22 in the upper end of the spindle 2, the lower end of said spring bearing against a shoulder in the spindle, and the upper end against a pin in the rod 16. The rod 16 is slotted for the passage of the pin 6b, to permit of the vertical adjustment of said rod.

The frames 9 have recessed end projections 23, encircled by coiled springs 24, which hold said frames yieldably from expansion. The lower end of the cone 15 is also provided with a guide 25, slidable in the lower end of the cylinder 7.

It will be noted that each of the frames 9 has a triple bearing, one at each end, and one medially thereof through the contact of the follower 14 against the cone 15.` This assists in holding the grinding elements in proper position and with a uniform operation thereof throughout their lengths.

In the operation of the machine, the grinding tools are introduced into the cylinder or other piece of work in the usual manner, and the frames 9 and grinding elements graduallyV expanded as the work progresses, by downward adjustments of the rod 16. By the movement-of said rod in the opposite direction the cone 15 is withdrawn, permitting the return of the frames to their former position, this return being compelled by means of the springs 24. If desired, the action of the rod may be automatically controlled, by the means set forth in said former application, and partly shown herein.

What I claim, and desire to .secure by Letters Patent, is:

1. In a cylinder grinding tool, expansible abrading elements, a support for said elements. means for connecting said support to a source of power for rotary movement thereof, including a hollow intermediate shaft and a joint affording` universal action, means in said support for adjusting said elements, a spring-pressed adjusting rod within said hollow shaft connected at one end to said element-adjusting means and at its opposite end extending beyond said hollow shaft, said rod being rotatable with said hollow shaft and axially movable relative thereto, and a manually operable adjusting element engaging the outer end of said adjusting rod for eiecting axial movement of said rod.

2. In a cylinder grinding tool, expansible abrading elements, a support for said elements, means for connecting said support to a source of power for rotary movement thereof, including a hollow intermediate shaft and a joint aording universal action, means in said support for engaging and adjusting said elements, an adjusting rod within said hollow shaft and connected at one end with said element-adjusting means and at its opposite end extending beyond said hollow shaft,

said rod being rotatable with said hollow shaft and axially movable relative thereto, spring means engaging said rod for extending said rod to element-contracting position; a manually operable adjusting element engaging the outer end of said adjusting rod for effecting axial movement of said rod, and spring means forl contracting said elements.

3. In a cylinder grinding tool, expansible abrasive carriers, a support for said carriers, a hollow drive shaft connected to said support, means on said support for adjusting said carriers, an adjusting rod within said hollow shaft connected at one end to said carrieradjusting means and at its opposite end `extending beyond said hollow shaft, said rod being rotatable with said hollow shaft and axially movable relative thereto, and a manually operable adjusting element engaging the outer end of said adjusting rod for effecting axial movement of said rod.

WILSON P. HUNT. 

